WIND anp WATER-SPOUTS, &c. 347 
muft naturally be very different. Here are no accumula- 
tions aloft. The quantity ready for a difcharge downward 
is vaftly lefs, and the paflage narrow and contracted ; and 
by the almoft conftant motions of air, were there more 
fupplies it would foon fhut up. Befides there is little apt- 
nefs to flow from furrounding regions by reafon of the 
fmallnefs of their depth, &c. And yet fo great is the fpe= 
cific weight of what defcends, that the firft aflault has been 
known to equal the greateft violence of the proper hurri- 
canes in their moft powerful moments, 
N° XLI. 
The whole Procefs of the Silk-Worm, from the Egg to the 
Cocon ; communicated to Dr. JOHN MorGAN, Phyfici- 
an at Philadelphia, in two Letters from Mefrs HARE 
and SKINNER, Silk Merchants in London, Fuly 27,5 
1774, and February 24, 1775+ 
Read July 
Sie [1 is fome time fince we were honored with your 
efteemed letter of 27th September laft. We 
fhould not have delayed fo long acknowledging its receipt, 
if it had been in our power to have fent you before this 
time the manufcript you will receive herewith ; but it is 
only lately we have been able to procure it from one of 
the firft houfes in Italy. It contains an exact account of 
the Italian moft improved method of making raw filk. 
We flatter ourfelves it may prove of fome fervice to your 
new eftablifhed manufaCtory, for whofe ufe folely we fent 
for it to Italy. 
The large quantity of raw filk that continually arrives 
from China every year, being moftly of a round or large 
fize, will a good deal interfere with the fale of yours, 
provided 
